- From: Ashok Malhotra <ashokma@microsoft.com>
- Date: Tue, 17 Sep 2002 08:25:22 -0700
- To: "John Mercado" <johnkmercado@yahoo.com>, "W3C XML Schema Comments list" <www-xml-schema-comments@w3.org>
- Message-ID: <E5B814702B65CB4DA51644580E4853FB03E9FE31@red-msg-12.redmond.corp.microsoft.com>
There is no canonical form for duration since there is but a single lexical representation. The lexical forms P1Y and P12M map to different values. Some people had problems with this datatype since it does not have a total order. To solve this problem we defined two subtypes of duration called dayTimeDuration and yearMonthDuration that have a total order and correspond to similarly named SQL types. All the best, Ashok =========================================================== Ashok Malhotra <mailto: ashokma@microsoft.com <mailto:%20ashokma@microsoft.com> > Microsoft Corporation 212 Hessian Hills Road Croton-On-Hudson, NY 10520 USA Redmond: 425-703-9462 New York: 914-271-6477 -----Original Message----- From: John Mercado [mailto:johnkmercado@yahoo.com] Sent: Tuesday, September 03, 2002 10:04 AM To: W3C XML Schema Comments list Subject: What is the canonical lexical representation of duration? Hi, What is the canonical lexical representation of duration?, and how do I get there from any other lexical representation. I ask because I am trying to understand the XQuery yearMonthDuration and dayTimeDuration types. Those two types have a canonical form that converts, for example, P1Y to P12M. So, there is only one value in the value space that equals this amount of time. This makes sense, but it is not the way I thought the XML Schema types worked. Are the duration values P1Y and P12M considered to be the same value? If so, how do I know which one is the canonical form? The rec doesn't say anything about this. If not, isn't the XQuery spec in direct violation of the XML Schema spec for converging values in the value space? This question aside, there is also the minor point of other different lexical representations (e.g. leading zeros in the number values, trailing zeros in the number of seconds) that would also need to be clarified when deciding on the canonical representation for duration. Thanks, John Mercado Do You Yahoo!? Yahoo! Finance <http://rd.yahoo.com/finance/mailsig/new/*http:/finance.yahoo.com> - Get real-time stock quotes
Received on Tuesday, 17 September 2002 11:25:54 UTC